Crystal Structure Solid-State Cross Polarization Magic Angle Spinning 13C NMR Correlation in Luminescent d10 Metal-Organic Frameworks Constructed with the 1,2-Bis(1,2,4-triazol-4-yl)ethane Ligand

Hydrothermal reactions of 1,2-bis(1,2,4-triazol-4-yl)ethane (btre) with copper(II), zinc(II), and cadmium(11) salts have yielded the dinuclear complexes [Zn2Cl4(mu(2)-btre)(2)] (1) and [Zn2Br4(mu(2)-btre)(2)] (2), the one-dimensional coordination polymer (1)(infinity)[Zn(NCS)(2)(mu(2)-btre)] (3), the two-dimensional networks (2)(infinity)[Cu-2(mu(2)-Cl)(2)(mu(4)-btre)] (4), [Cu-2(mu(2)-Br)(2)(mu(4)-btre)] (5), and (2)(infinity){[Cd-6(mu(3)-OH)(2)(mu(3)-SO4)(4)(mu(4)-btre)(3)(H2O)(6)](SO4) center dot similar to 6H(2)O} (6), and the three-dimensional frameworks (3)(infinity){[Cu(mu(4)-btre)]ClO4 center dot similar to 0.25H(2)O} (7), (3)(infinity){[Zn(mu(4)-btre)(mu(2)-btre)](ClO4)2} (8), (3)(infinity){[Cd(mu(4)-btre)(mu(2)-btre)](ClO4)(2)] (9), and (3)(infinity)[Cu-2(mu(2)-CN)(2)(mu(4)-btre)] (10, 2-fold 3D interpenetrated framework). The copper-containing products 4, 5, 7, and 10 contain the metal in the +1 oxidation state, from a simultaneous redox and self-assembly reaction of the Cu(II) starting materials. The cyanide-containing framework 10 has captured the CN- ions from the oxidative btre decomposition. The perchlorate frameworks 7, 8, or 9 react in an aqueous NH4+PF6- solution with formation of the related PF6--containing frameworks. The differences in the metal-btre bridging mode (mu(2)-kappa N1:N1', mu(2)-kappa N1:N2 or mu(4)-kappa N1:N2:N1':N2') and the btre ligand symmetry can be correlated with different signal patterns in the C-13 cross polarization magic angle spinning (CPMAS) NMR spectra. Compounds 2, 4, 5 and 7 to 10 exhibit fluorescence at 403-481 nm upon excitation at 270-373 nm which is not seen in the free btre ligand.